Currently, the existing liquid crystal display only has one group of gamma voltages, and generally, an optics engineer may only adjust a gamma curve with respect to a central point of the display panel, causing an optimal display effect (gamma value: 2.2) at a central region of the panel, while a relatively bad display effect at both sides of the panel. For example, a module of a sheet of display panel is measured, and the gamma curves of the central point and other four positions (as shown in FIG. 1) are taken as examples. As shown in FIG. 2, the gamma curve of the central point has been adjusted to be optimum, and the gamma curves of the other four positions can be obtained through measurement. The following conclusion can be reached: the further the measuring position is away from the central point, the more the gamma curve will deviates from 2.2.
A Chinese patent application numbered 201510387860.X discloses a gamma adjustment method of liquid crystal display panel, the method including the following steps: dividing a display region of the liquid crystal display panel to obtain n sub display regions; dividing a full gray-scale image into n groups to obtain n gray-scale image groups; making the n sub display regions display a first selected gray-scale image in a corresponding gray-scale image group simultaneously; utilizing photoelectric sensors arranged on the sub display regions (normally the central region) to detect the brightness of the first selected gray-scale image; obtaining the gamma curve of the liquid crystal display panel according to the gray scale of the first selected gray-scale image and the brightness of the first selected gray-scale image; and adjusting the gamma curve of the liquid crystal display panel according to a preset gamma curve. However, the above method cannot adjust the gamma curve with respect to the different regions of the display panel.
In the prior art, the generally used gamma adjustment method is used to adjust a gamma voltage only with respect to the central point of the display panel. FIG. 1 is a view of a plurality of positions on the liquid crystal display. FIG. 2 is a gamma curve graph adjusted by using the above curve adjustment method with respect to the plurality of positions in FIG. 1.
As shown in FIG. 1, the central point is located at a central position of the display panel, positions 1, 2, 3 and 4 deviate from the central point in sequence, and the display effect of the entire display panel is adjusted by adjusting the gamma curve with respect to the central point. Normally, a standard gamma value of the liquid crystal display is 2.2, and an optimal display effect can be achieved under such value. In this embodiment, the gamma value of the central point is made to be equal to or close to 2.2 through adjusting the gamma voltage. As shown in FIG. 2, the further the position is away from the central point, the more the measured gamma curve will deviates from 2.2, that is, the more the position deviates from the central region, the worse the display effect thereof will be. Thus it can be seen that, the display effect of the entire display panel can be hardly guaranteed by only adjusting the gamma voltage of the central point, and especially with respect to different regions, as the position deviates from the central point, the display effect thereof will also deteriorate.
Thus in terms of adjusting the display effects of different regions of the display panel, the existing gamma adjustment method has many defects. Thus it has become a major problems in the prior art how to adjust the gamma curve of the display panel more effectively and perform gamma adjustment with respect to different regions so as to improve the display effect.